Conventionally, there has been liquid chromatography using a principal of liquid chromatography in which a cylindrical container, called a column, having a liquid inlet and outlet in the center of an upper and lower circular plates, is filled with a particulate filler, called a gel, having a particle diameter of ten to several hundred microns, so that separation/purification of a substance is performed utilizing the interaction between solute molecules and conclusion when a liquid is made to flow from either the upper or lower liquid inlet or outlet by a pump or the like. Currently, various gels for liquid chromatography having different surface structures are commercially available. Gels whose surface displays ion exchange groups, function as an ion exchange gel, which is capable of separation of a substance by means of ion exchange chromatography utilizing the interaction of ionic charges with solute molecules.
Incidentally, these chromatography separation systems have been applied as a system of a complicated structure combined with; a pump for making liquids flow through the column, a container for containing these liquids, a valve for appropriately switching the passage, and measuring equipment for detecting the absorbance, pH, the electrical conductivity of an object substance flowing out from the column.
Normally, separation of a substance in chromatography involves a method for combining columns at several steps to achieve a required purified purity. Two or three steps of chromatography are often combined such as ion exchange chromatography→hydrophobic chromatography→gel filtration chromatography. However, in reality, when a substance is searched for and examined for use in research and development, only one or two steps of chromatography are sufficient in many cases. However, even when only one step of chromatography is performed, there is a problem in that the liquid chromatography system is likely to be a large scale system combined with a pump, a passage switching system, a column, containers for chromatography developing solutions, a detection system, and the like.
Moreover, even in such a large scale system, each specimen can be treated only one by one. Therefore in conventional liquid chromatography there is also a problem in that the treatment efficiency is low. Moreover there is a problem in that the flow direction is limited to one way only.    [Non Patent Document 1] “Liquid Chromatography Q&A” (published by Gihodo Shuppan Co., Ltd., June 2006, written by Itaru Matsushita)    [Non Patent Document 2] “Reality of Liquid Chromatography” (published by Sankyo Publishing Co. Ltd., 1976, written by Akira Etoh)